We know that a piece of toast, if dropped, will fall butter-side down. We also know that a cat, if dropped, will land on its feet. What happens when you strap a piece of buttered toast to a cat's back and drop them both is called the Buttered Cat Paradox, and there's an extensive amount of research on the internet devoted to just this conundrum. Find out more about it at mental_floss, including possible uses for the energy produced from such a venture, and ways it could go wrong. Link